Refrigeration apparatus



C?- 1936. D. HEATH REFRIGERATION APPARATUS Original Filed Jan. 2, 1951(kKM Patented Oct. 27, 1936 PATENT FFlCE REFRIGERATION APPARATUS DelosP. Heath, Detroit, Mich.

Application January 2, 1931, Serial ,No. 506,287 Renewed April 12, 19348 Claims. (Cl. 62-126l This invention relates to refrigerators and is ofparticular use in the construction of refrigerantheat exchangers. It isan object to provicle a system of cooling a refrigerator, wherein a 5sheet metal corrugated wall expansion chamber is provided as a heatexchanger within the refrigerator.

It is an object to provide a heat exchanger structure that may bereadily formed from one sheet of metal, and which is convenientlyadaptiiiin these corrugations or expanding therein may have its rate ofebullition accelerated. I

As disclosed in my application, Serial No. 450,861, flied March 9, 1921,and as shown in my Patent No. 1,726,486, of August 27, 1929, 1 havefound a corrugated sheet metal refrigerant ere pension chamber, emcientand cheaper to build than the usual copper tube coil, or a cast ironevaporator, and it is now the purpose or this specification to recitecertain improvements in A construction or the evaporator itself and todisclose certain uses of this evaporator in multiple arrangement, whichI have found to be most omcient.

In the drawing:

1 is a plan view of the single sheet evaporator, after corrustatlne, butbefore bending.

Fig. 2 is a sectional view and elevation alone 35 line hit of Fig. 1,after dine the single sheet evaporator.

Fig. 3 is a perspective view of a modification oi Fig. 1, showing theevaporator formed or two sheets.

, Fig. l is'a perspective view showing the multi- 1 pie assembly of theevaporators in a vertical position within a refrigerator, andoperatively connected to a motor-compressor=condenser float controlsystem exterior to the refrigerator.

Fig. 5 is a perspective View, showing .a-multi ole arrangement of theevaporator in a horizontal position, within a refrigerator, andoperatlvely connected to a float within the refrigerator, and a motorcompressor-condensersystem exterior to the refrigerator heat insulation.1

Fig. 6 shows a cross section in'elevation along line AA of Fig. 1, and.illustrates a modification of the corrugation in the walls of the tankto provide a space of varying cross sectional, area.

The device-may. be formed of any material till able for multipleassembly, either ina vertical or I this modification, the ends or swhich may be rolled into a. sheet form, pressed, bent and fixed orwelded together between the corrugations and at its periphery. However,I prefer to form mytanlr or sheet steel and to m the walls together bythe welding process.

Like reference characters, refer to like parts in the different figuresof the drawing. 1! indicates a sheet which may be of any outline, but isbest out in a rectangular shape.

2 and t arecorrugations formed in l by the stamping process, or by othermethods. The oorrugations 2 connect with thespace within corrugation t.The sheet is then bent to form the nections for the inlet refrigerantliquid and the outlet expanded refrigerant gas respectively.

In. Fig. 3 I show a modification in which sheet l is corrugated with notonly corrugations t and t, hut also corrugation t, and a sheet t iswelded to sheet lto form the expansion chamber. In and it are closed bythe metal of l during terms, and openings l and t are made in El and tior the passage of the refrigerant into and. out of the evaporator.Nilmoral t is an expansion valve.

lnj ia. e the evaporator l is connected in multlple by the L tubes ii atthe corrugations t and Any number oi the vertical evaporator sec tionsLmay he assembled inthis manner. The conduit it admits liquidrefrigerant and the conduit it draws oh the expanded refrigerant gas,returning it to compressor it, which is driven Toy motor it. Fan it isalso driven by motor it and cools condenser it which hows its liquidreerant float valveplaced at the proper level within the refrigeratorit, in respect to evaporator l, to maintain a uniform level of liquidrefrigernot within theicorrugated walls of l. ltl'represeats a liquidrefrigerant receiver.

in operation, the motor compressor unit in Figure 4 withdraws gaseousrefrigerant from dome corrugation t, causing the liquid refrigerant inthe vertical corrugations 2 to boil, because thepressure is loweredin'the evaporator. Heat is removed from the refrigerator ID by thisboiling refrigerant, and carried to the condenser I! where therefrigerant is cooled by the fan It, or by other suitable means, andagain condensed to a liquid which flows into the shell of float valvell, causing the float to rise and Open its valve in the customarymanner. The liquid refrigerant then fiows thru conduit l2 into thehorizontal headers, l of the multiple assembly of the evaporator l.Articles may be placed within the compartment formed by adjacent unitsof the multiple evaporator assembly for the purpose of cooling themrapidly or freezing them. I have provided shelves 2i for the purpose ofeiiiciently conducting the heat away from articles placed on them, tothe'inwardly projecting horizontal headers 3. Because liquid refrigerantis under the shelf in intimate thermo-relationship with the material ofthe shelf, or the material of a removable tray such as 22, cooling andfreezing: operations take place in a minimum of time.

In Fig. 5, the corrugations 2 of the multiple evaporators i, aresubstantially in a horizontal position, and this arrangement thereforeprovides a support for articles to be frozen, directly in contact with alarge area of the evaporator I. The large size of the header 5 permitsit to serve as a gas dome that the boiling liquid within the evaporatormay not prime over into the gas section line of the compressor l4. Thehead-, er 3 and the corrugations 2 in this construction are placed atthe bottom, that a slightly upward flow of gas may be permitted. In theoperation of the system, shown in Figure 5, the evaporator,motor-compressor-condenser unit act as before described, but therefrigerant float valve control is within the refrigerator Ill andadmits liquid refrigerant when the compressor ll has drawn oflsufiicient gas to reduce the liquid level in the evaporator I and theshell of the low pressure float 20.

Fig. 6 construction provides that the corrugation 2 be varied in crosssection and increasing in size from header 3 to the header 5. Thisallows accelerated boiling action, as the bubbles of gaseous refrigerantformed within the liquid refrigerant within the corrugations 2 rapidlyincrease in size and in passing to header 5, tend to drive liquid aheadof them in the well known percolator action. This work done by theboiling liquid refrigerant is minimized if space may be provided for thebubble of gas and also space for the liquid refrigerant which remainsbehind within the same corrugation. It is also possible to keep themaximum amount of surface of the corrugations 2 as wet surface forbetter heat transmission with the tapered construction, as shown inFigure 6.

The construction described is of light weight and great strength, andcan be most economically produced and efficiently operated. I find thatit may be made of materials of a rust-proof nature, or,of material suchas steel, which may be protected by rust-proof processes. The steelconstruction is particularly adapted for welding, and for porcelainenameling. As the interior surfaces of a refrigerator food chamber mustbe cleaned at frequent intervals to maintain sanitary conditions, Iprefer to make my evaporator of steel and of a wall thickness which willpermit a structure that is not subject to serious deflection underpressure conditions, and which will be satisfactory to receive the bakedporcelain enamel.

The invention is defined in the following claims,

1. In a refrigeration apparatus a refrigerator having a heat insulatedchamber, a refrigerant condensing unit exterior to said chamber, aflooded type refrigerant evaporator within said chamber operativelyconnected to said condensing unit, said evaporator comprising aplurality ofadjacent fiat walled sheet metal expansion chambers arrangedin substantially a horizontal plane, each of said chambers having aplurality of substantially parallel corrugations terminating intransverse headers embossed at opposite ends of the chamber, the wallsof said chambers being fused together at contiguous fiat portionsbetween the corrugations and at or near the peripheries of the chambers.

2. In a refrigeration apparatus, a refrigerator having an insulatedcompartment, a refrigerant liquefying and condensing unit exteriorly ofsaid compartment an evaporator within said compartment and connected tosaid unit, said evaporator including a plurality of horizontallydisposed substantially flat plate-like double walled members having aplurality of parallel corrugations formed in a wall thereof and definingrefrigerant expansion passages, said plurality of expansion passagesterminating in transverse headers embossed in a wall of the plate-likeevaporator members, the walls of said plate-like members being securedtogether at or near their peripheries and at contiguous portions betweenthe corrugations, and said plurality of fiat plate-like evaporatormembers being disposed in substantially the same horizontal plane andhaving means inter-connecting the same to maintain a common refrigerantlevel therein.

3. An evaporator for a refrigerating system comprising a single sheet ofmetal bent to provide a header and having continuations thereof pressedinto face-to-face relationship and secured together and defining acontinuous radiating surface extending from the header, saidcontinuations having corrugations formed therein defining passagewayscommunicating with said header, and said passageways formed by thecorrugations being of gradually increased cross-sectional tinuationshaving corrugations formed therein defining a second header smaller thansaid first named header and a plurality of passageways communicatingwith both of said headers, and said passageways formed by thecorrugations being of gradually increased cross-sectional area from saidsecond named header to said fifst named header. I 5. An evaporator for arefrigerating system comprising, sheet metal portions secured togetherin, face-to-face relationship, one of said sheet metal portions having a-corrugation formed therein providing a header, one of said sheet metalportions having a plurality of corrugations formed therein and providinga plurality of passageways communicating with said header, and saidpassageways being of gradually increased cross-sectional area towardsaid header. 6. An evaporatorfor a refrigerating sys 55 ing surface.extending from the header, said con- 1 comprising, sheet metal portionssecured together in face-to-Iace relationship, one of said sheet metalportions having corrugations formed therein providing spaced apartheaders, one of said sheet metal portions having a plurality ofcorrugations formed therein and providing aplurality of passagewayscommunicating with' the spaced apart headers, and said passageways beingof gradually increased cross-sectional area toward one of the spacedapart headers.

7. An evaporator for a refrigerating system comprising, sheet metalportions secured together in iace-to-face relationship, one of saidsheet metal portions having a corrugation formed therein providing aheader, one of said sheet metal portions having acorrugation formedtherein providing a second header spaced from said first named header,one of said; sheet metal formed therein and providing a plurality ofpassageways extending between and communicating with the spaced apartheaders, andsaid passageways being of gradually increasedcross-sectherein providing an upper header, one of said sheet metalportions having a corrugation formed therein providing a lower headerspaced-from said upper header, one of said sheet metal portions having aplurality of corrugations formed therein and providing a plurality ofpassageways extending between and communicating with the spaced apartheaders, and said passageways being of gradually increasedcross-sectional area toward the upper header.

Q l James P. HEATH. 20

